The present invention relates to implosion-resistant cathode ray tubes and more particularly to implosion-resistant cathode ray tubes having a panel member with a relatively smooth skirt portion whereon a pair of rimbands having affixed brackets are adhesively attached and compressively held by an encircling strap member.
The present art suggests a number of implosion-resistant cathode ray tube structures. One known technique requires a metal band which encircles the face plate of the tube and is shrunken to provide a compressive force thereon. Another technique provides a first and second tension straps applied on top of one another.
In still another technique, rimbands contoured to conform to the viewing panel of a cathode ray tube are affixed thereto. Such rimbands are utilized with face plate members having a mould line and are disposed thereover in a manner such that the uneven surface of the mould line assists in maintaining the positional location of the rimband when a strap member is employed to effect a compressive force thereon.
Although the above-mentioned techniques have been and still are employed in numerous operations for fabricating implosion-resistant cathode ray tubes, it has been found that some tubes present special problems. Thus, the usual techniques are insufficient to provide the desired and required implosion protection.
More specifically, it has been found that the above-described contoured rimbands are relatively expensive to fabricate or purchase. Also, contoured rimbands have a tendency to "buckle" or deviate from the exact contour of the face plate whenever a compressive force is applied to the rimbands. Further, it has been found most difficult to maintain the positional location of rimbands on cathode ray tubes having a smooth skirt surface without a mould line. Moreover a separate safety panel cannot be used with contoured rimbands because of interference therebetween.